Formation, distribution, and photoreaction of nano-sized vanadium oxide cluster anions.

It is experimentally challenging to generate nano-sized metal oxide clusters with significant intensity as well as to resolve a single hydrogen atom by mass spectrometry (TOF-MS). Herein, the high-resolution tandem time-of-flight mass spectrometer is home-made and the experimental apparatus is capable to perform the reactivity study of nano-sized vanadium oxide clusters. The formation and distribution of nano-sized vanadium oxide cluster anions V x O y − ( x up to 70) were analyzed and the photoreaction of alkene attached complex V 40 O 101 C 2 H 4 − (or V 40 O 101 C 3 H 6 − ) was studied. Larger V x O y − cluster anions can be generated typically under higher O 2 concentration and the intensity proportion (%) of vanadium oxide cluster with a certain oxygen-deficiency value Δ (Δ= 2 y -5 x -1 for V x O y − ) in each V x series is nearly invariant. In photoreaction of V 40 O 101 C 2 H 4 − (or V 40 O 101 C 3 H 6 − ), the transfer of two oxygen atoms from V 40 O 101 − to C 2 H 4 (or C 3 H 6 ) and the generation of V 40 O 99 − dominants the channel. The mass resolution of the primary TOF-MS for V 40 O 101 − (∼1.5 nm) is up to 13002. The mass resolution of the secondary TOF-MS for photoreaction is calculated to be about 4530 to resolve parent (V 40 O 101 C 2 H 4 − ) and daughter ions (V 40 O 99 − ). [ABSTRACT FROM AUTHOR]